1. Field of the Invention
This invention generally relates to audio electrical devices and, more particularly, to a system and method for detecting the type of headset connected to an audio electrical device.
2. Description of the Related Art
The following discussion is directed to wireless communications devices. However, it should be understood that the discussion applies to other types of electronic devices as well. Wireless communications devices are being developed to perform functions beyond those associated with traditional voice communication. Among those functions is the ability to provide audio signals to a headset plugged into the device. To perform audio functions properly, to manage energy consumption in the wireless device, and to prevent damage to circuitry caused by the application of incompatible signals, the device must be able to distinguish a stereo headset from a different type of accessory, for example, a mono headset, plugged into a device interface port. For example, supplying a stereo signal to a mono headset wastes energy in the device and supplying a mono signal to a stereo headset fails to utilize the features of the headset. At the same time, wireless device users demand smaller and more inexpensive devices with added capabilities, creating in turn, a need to reduce the number and cost of components in the device. An undesirably large number of components are typically used in a wireless device to identify the type of accessory plugged into the device. Unfortunately, increasing the number and complexity of components in a device can limit the size to which the wireless device can be reduced and can add to the cost of producing the wireless device.
It would be advantageous if a wireless communications device could identify the type of headset plugged into the device using a minimal number of relatively simple components.